Either the game will support 4:3, and it'll look fine, or there will be borders above and below the image. Either way you shouldn't get a squashed image.
No word on any VGA cables yet (I dont think) That's what you're looking for right?
Well they are releasing component cables, so you could just buy component to VGA adapter and plug it into the back of your monitor and voila, Wii goodness on your screen.